Valve means for suction lifting devices



Feb. 26, 1957 e. F. LYTLE VALVE MEANS FOR SUCTION LIFTING DEVICES Filed Feb. 11 1955 INVENTOR Geofge FLyi'le 6 NUNDQW Eabucs OF ATTORNEY nite States Patent VALVE MEANS FOR SUCTION LIFTING DEVICES George F. Lytle, Salem, Ill., assignor to Vac-U-Lift Company, Salem, 11]., a corporation of Illinois Application February 11, 1955, Serial No. 487,503

1 Claim. (Cl. 251-25) This invention relates to pneumatic lifting devices and is more particularly concerned with improvements in vacuum or suction lifting devices.

Suction lifting devices of the type referred to comprise, in general, a suction pad formed of a plate member, a flexible air impervious annular skirt on one side of the plate, a platen on the interior of the skirt secured both to the skirt and the plate, a tubular nipple having one end disposed through and connected to the platen, the other end of the nipple being adapted for connection to a hose leading from a valve in a pneumatic system and by means of which vacuum or air under superatmospheric pressure may be selectively applied to the interior of the pad for quick application and release of the-pad to an object to be lifted.

One of the objects of the present invention is the pro vision of a special valve means in connection with the nipple and hose for insuring a more positive action in the application and release of suction.

Another object of the present invention is the provision of such valve means which obviates the need for any superatmospheric pressure, thereby making it possible to operate the device by connection to a suction line only.

A further object of the invention is the provision of a special type valve means of the type mentioned containing novel features of construction, arrangement of parts, and operation adaptable to industrial application.

Other objects and advantages of the invention will be apparent from the following description considered together with the accompanying drawing.

In the drawing:

Fig. 1 is a vertical sectional view of a suction pad in accordance with an embodiment of the invention in the suction breaking position and a portion of the pneumatic system associated therewith.

Fig. 2 is a View similar to Fig. l in the vacuum drawing position.

Fig, 3 is a schematic diagrammatic view of the control valve of Fig. 1 in the position for drawing vacuum on the suction pad.

Fig. 4 is a view similar to Fig. 3 in the suction breaking position.

Referring with more particularity to the drawing in which like reference characters designate like parts, the embodiment illustrated comprises the general suction pad structure, namely, a ring member if, the annular flexible cushion or pad member 12 of rubber or other suitable material having a flat annular portion 13 set against the ring 11 and a circular skirt portion 14 projecting downwardly and outwardly thereof. The skirt portion is tapered by a convex curving 15 along the inner wall and bottom.

The annular portion 13 has an inwardly projecting flange or lip 16 and against the bottom of this lip, a platen 17 is disposed and firmly secured to the ring 11 by means of bolts 18.

The platen 17 is integral with a boss or block portion M 2,783,018 Patented Feb. 26, 1957 19 which projects upwardly and is secured to a lifting arm or rod 20.

The lower end of a tubular nipple 21 is disposed in an aperture 22 of the platen 17 to communicate with the underside thereof. The upper portion of the nipple 21 extending above the platen 17 is connected to a bottom chamber 23 of the valve body 24. A pipe line 25 is tapped in on one side of the valve body to communicate With the chamber 23. Above the chamber 23 there is formed an annular valve seat 26 for a valve plunger 27. Above the valve seat 26, one or more side vents 28 are provided in the valve body.

The valve plunger 27 is connected to the bottom of a vertical stem 29. The upper end of the stem 29 is secured to a flexible diaphragm 30 of rubber or other suitable lines 34 and 25 and two additional pipe lines 41 and 42,

respectively, are connected.

The pipe line 41 is open to the atmosphere and the pipe line 42 extends to a source of vacuum or subatmospheric pressure (not shown) When the solenoid spool member 36 is moved to one position, represented by Fig. 3, the pipes 25 and 41, leading to the pad and atmosphere, respectively, are blocked, While the pipes 34 and 42 are placed in communication with each other, whereby the top of the diaphragm 3% is communicated with the source of vacuum. This causes atmospheric pressure against the bottom of the diaphragm acting through the vents 28 to elevate the plunger 27 from its seat and break the vacuum in the pad quickly by virtue of the short communication between the interior of the pad and the atmosphere through the said vent.

When the solenoid spool member 36 is moved in the opposite direction, to the position illustrated in Fig. 4, the space in the arched section 33 above the diaphragm 30 is communicated with the atmosphere through the pipe line 41, thus breaking the vacuum therein and causing the plunger 27 to drop onto its seat 26. At the same time, the pipe 25 is connected to the pipe 42 from the vacuum source, whereby the interior of the pad is maintained under suction to hold and lift an object 43 until it is desired to release it, whereupon the member 36 is again shifted to the position shown in Fig. 3.

I claim:

A valve device for the suction pad of a suction lifting device comprising a valve body having a chamber at the bottom and a valve seat above the chamber, a valve plunger normally resting on said seat when the valve is in its closed position, a valve stem connected to the plunger and projecting upwardly therefrom, a flexible diaphragm above the plunger, said stem being connected to the diaphragm for movement therewith, a member above said diaphragm having a space in communication with the top of said diaphragm, means for communicating a first external pipe with the interior of said space, means for communicating a second external pipe with the said chamber, said body having also a vent opening between the seat and the diaphragm, a manifold memher having a pair of ports connected to said external pipes, respectively, and a second pair of ports for connection to a source of vacuum and to the atmosphere, re spectively, and a movable spool member within said manifold, said spool member having separate recesses cooperating with said ports, said recesses being of such lengths that the spool member in one position inter-relates the ports so that the first external pipe is connected with the atmosphere While the second external pipe is connected to the source of vacuum and, in another position, to interrelnte two of the ports so that the first external pipe will be intercommunicatcd with the source of vacuum and to block the other ports.

References Cited in the file of this patent UNITED STATES PATENTS 1,205,898 Jones Nov. 21, 1916 1,496,391 Thomas June 2, 1924- 2,177,099 Dreyer Oct. 24, 1939 

